When combating wildfire from the air, various tools can be utilized. One common tool is to load an appropriately configured aircraft with water or wildland fire chemicals, fly the aircraft over the fire or an area adjacent the fire to be protected, and discharge the fire chemical or water from the aircraft. While fire chemicals are quite effective in suppressing wildfire, the aircraft must travel to a reloading base and return to the location of the wildfire before additional loads can be dropped, decreasing the effectiveness of such aircraft proportional to the distance the reloading base is from the fire and the time such reloading takes.
In many instances bodies of water are available in the area where the wildfire is occurring. Helicopters can be utilized with buckets suspended therefrom which can be loaded with water and then flown to the site of the wildfire and released. Helicopters and other rotary wing aircraft are also known to have a fixed tank thereon for fire chemical or water. One filling method for such fixed tanks is to utilize a snorkel extending down from the tank with a pump at the lower end to allow the tank to be filled from bodies of water close to the fire. Water is not as effective as fire retardants, suppressants or other fire chemicals in combating wildfire. Also, helicopters generally have a lesser payload capacity than airplanes.
Water's effectiveness as a fire suppressant can be significantly enhanced by adding a suppressant polymer to the water. One such polymer material is provided under the trademarks FIREWALL ULTRA, provided by BroadRange Wildland Fire Chemicals of Cold Springs, Calif. and FIREWALL II, provided by Eco FireSolutions of Carmichael, Calif. One unique characteristic of such polymer material is that merely adding the polymer material to water does not provide the full benefit of fire suppressant capacity to the water. Rather, the polymer must be both activated and thoroughly mixed with the water. Shearing forces cause the water to have the polymer fully activated as a first part of the polymer preparation process, so that the fire suppressant effect of the water can be maximized. A second part of the preparation process is mixing to distribute the activated polymer throughout the water load. A pump is typically used which provides the required shearing/mixing force to activate the polymer.
In some instances a fire fighting aircraft with a tank may benefit from first taking on a load of water and later, at the option of the operator, having polymer gel emulsion added to the water within the tank and activated and mixed with the water shortly before the water and polymer gel emulsion are to be dropped. With such a delayed addition of polymer gel emulsion to water within the tank, along with activation and mixing thereof, an operator has the opportunity to take on a load of water in a first step and not have the polymer gel emulsion immediately added thereto. Then, should the load of water not be needed for firefighting, the polymer gel emulsion has not been wasted and the water can be dropped without concern for polymer release into the environment. Furthermore, should an operator determine that polymer gel emulsion is not needed, water can be dropped without polymer gel emulsion. Furthermore, an operator can determine shortly before dropping water with polymer gel emulsion how much polymer gel emulsion to add to the water.